EFFECTS OF DECAFFEINATED GREEN TEA (CAMELLIA SINENSIS) ON REPRODUCTIVE CHARACTERISTICS AND EGG QUALITY IN RAINBOW TROUT (ONCORHYNCHUS MYKISS)

摘要

This study investigated the effects of dietary decaffeinated green tea (Camellia sinensis) in female broodstock of rainbow trout on their reproductive performance and subsequent egg quality. Commercial diet with 100 mg.kg –1 feed decaffeinated green tea extract was prepared. Sixty rainbow trout (2475.5 ± 64.4 g) were randomly allocated to 2 groups in triplicates and fed diet containing 100 mg kg -1 decaffeinated green tea or control diet for 30 days. On days 20 and 30 during feeding trial, mature fish were weighed and sampled for stripping. Results showed that reproductive performance in terms of total egg weight, egg number per gramme and fecundity were not affected in treatment group. Level of glucose increased markedly on days 20 and 30 while on day 20 of feeding trial, triglyceride content in fish eggs showed a significant decrease. Lipid peroxidation products, indicated by malondialdehyde (MDA), significantly decreased in fish egg with 100 mg kg –1 feed adminis- tration, indicating elevated antioxidant status in treatment group. Slight increase in superoxide dismutase activity in treatment group was also revealed on day 20 of trial. These results demonstrated significant benefits of decaffeinated green tea extract supplementation of rainbow trout broodstock feed in terms of improved egg quality.